JPH114813A - Automatic blood pressure measuring device with function of displaying pulse wave intensity - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic blood pressure measuring device having functions whereby the intensity or magnitude of the pulse of a living body can be recognized objectively. SOLUTION: A maximum amplitude value AMmax of a cuff pulse wave determined by a maximum amplitude determining means 82 is displayed on a pulse wave display 44 or a recording paper of a printer 38 by a cuff pulse wave intensity display means (maximum amplitude display means 84). The maximum amplitude value AMmax of the cuff pulse wave shows the intensity of the current pulse wave, and when the blood pressure of a living body is measured by use of an automatic blood pressure measuring device, the strength or magnitude of the pulse of the living body can be sequentially recognized objectively whenever necessary. Thus in addition to the blood pressure value of a subject, the strength or magnitude of the pulse of the subject can be used as materials for diagnosis and medical judgment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic blood pressure measuring device having a function of displaying the intensity of a pulse wave of a living body when measuring the blood pressure value of the living body.

[0002]

2. Description of the Related Art In the process of changing the compression pressure of a cuff against a living body, a blood pressure value of the living body is measured based on a change in the magnitude of a cuff pulse wave, which is a pressure oscillation generated in the cuff in synchronization with a pulse. Automatic blood pressure measuring devices are known. An example is an oscillometric automatic blood pressure measurement device.

[0003]

Although the blood pressure value of the living body can be obtained by using the automatic blood pressure measuring device as described above, the size or strength of the pulse of the living body cannot be grasped. On the other hand, the finger can be pressed against the radial artery to recognize the size or strength of the pulse, but in such a case, it is necessary to sense the size or strength of the pulse sensuously. However, there is a problem that sufficient accuracy cannot be obtained due to the need for experience or variations in senses.
In the field of diagnosis and medical treatment, the size or strength of the pulse of a living body is important biological information in order to grasp the circulation dynamics of the living body.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an automatic blood pressure measurement apparatus having a function of objectively recognizing the strength or size of a living body pulse. Is to provide.

[0005]

The gist of the present invention to achieve the above object is to change the pressure of the cuff applied to the living body by using pressure oscillation generated in the cuff in synchronization with the pulse. A blood pressure measurement device that measures the blood pressure value of the living body based on a change in a certain cuff pulse wave, and (a) a cuff pulse wave detection device that sequentially detects a cuff pulse wave that is a pressure oscillation generated in the cuff, (b) cuff pulse wave intensity display means for displaying the cuff pulse wave intensity detected by the cuff pulse wave detection device on a display.

[0006]

In this manner, the cuff pulse wave intensity display means displays the intensity of the cuff pulse wave sequentially detected by the cuff pulse wave detector on the pulse wave intensity display. When measuring the blood pressure of a living body using the method, the strength or size of the pulse of the living body can be objectively and sequentially recognized.
Therefore, in addition to the blood pressure value of the subject, the strength or magnitude of the pulse of the subject can be used as diagnosis or medical judgment data.

[0007]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a diagram illustrating an electrical configuration of the automatic blood pressure measurement device 8.

In FIG. 1, an automatic blood pressure measuring device 8 has a rubber bag in a cloth band
2, a pressure sensor 14 and a switching valve 1 connected to the cuff 10 via a pipe 20, respectively.
6 and an air pump 18. The switching valve 16 has three states: a pressure supply state in which the supply of pressure into the cuff 10 is allowed, a slow discharge state in which the cuff 10 is gradually discharged, and a rapid discharge state in which the cuff 10 is rapidly discharged. It is configured to be switchable between two states.

The pressure sensor 14 detects the pressure in the cuff 10 and outputs a pressure signal SP representing the pressure to the static pressure discriminating circuit 22.
And the pulse wave discrimination circuit 24. Static pressure filter circuit 22 includes a low pass filter, steady pressure or cuff pressure P _C to discriminate the cuff pressure signal SK representative of the in the cuff pressure signal SK to the A / D converter 2 is included in the pressure signal SP
6 to the electronic control unit 28.

The pulse wave discrimination circuit 24 includes a band-pass filter, and frequency-discriminates the cuff pulse wave signal SM, which is the vibration component of the pressure signal SP, and converts the cuff pulse wave signal SM into an A / A signal.
The data is supplied to the electronic control device 28 via the D converter 29. The cuff pulse wave represented by the cuff pulse signal SM is a pressure vibration wave, that is, a cuff pulse wave transmitted from the brachial artery to the cuff 10 in synchronization with the patient's heartbeat, and periodically changes at the same frequency as the heartbeat. The cuff pulse wave signal SM after passing through the A / D converter 29 is a digital signal indicating an instantaneous value of the sampling cycle of the A / D converter 29 of several milliseconds to several tens of milliseconds. The resolution of the A / D converter 29 is, for example, 2
024 units, for example, 0 to 100 m
The output is changed in 2024 steps within the input span of V. In the present embodiment, the cuff 10, the pressure sensor 14, and the pulse wave discrimination circuit 24 function as a cuff pulse wave detection device.

The electronic control unit 28 includes a CPU 30, R
The microcomputer 30 includes a so-called microcomputer having an OM 32, a RAM 34, an I / O port (not shown), and the like. The CPU 30 executes signal processing using a storage function of the RAM 34 according to a program stored in the ROM 32 in advance. Thereby, a drive signal is output from the I / O port to control the switching valve 16 and the air pump 18 and also to control display contents such as numerical values or images displayed on the display 36 and the printer 38.

As shown in detail in FIG. 2, the display 36 is a systolic blood pressure display 4 for numerically displaying the systolic blood pressure.
0, diastolic blood pressure indicator 4 for numerical display of diastolic blood pressure
2, and at least a pulse wave amplitude display 44 for sequentially displaying the amplitude corresponding to the intensity of the cuff pulse wave and displaying the maximum amplitude corresponding to the maximum intensity of the cuff pulse wave. The pulse wave amplitude display 44 includes a plurality of rod-shaped light-emitting segments arranged in one direction, and turns on the number of light-emitting segments corresponding to the size of the cuff pulse wave signal SM, thereby generating the cuff pulse wave signal SM. At the same time as displaying the instantaneous value of the amplitude at the position corresponding to the maximum value of the cuff pulse wave signal SM.
The maximum value of the cuff pulse wave signal SM is displayed by lighting the light emitting segments.

FIG. 3 is a functional block diagram for explaining a main control function of the electronic control unit 28 in the automatic blood pressure measuring device 8. In the figure, the cuff pressure control means 72
During the measurement period of the blood pressure measurement means 70 activated at a predetermined cycle, the compression pressure of the cuff 10 is changed according to a well-known measurement procedure. For example, the cuff pressure control means 72 raises the cuff 10 to a target pressure set at about 180 mmHg, which is higher than the systolic blood pressure of the living body. Gradually lower the pressure at a speed of about sec,
When the blood pressure measurement is completed, the pressure of the cuff 10 is released. The blood pressure measuring means 70 determines the systolic blood pressure value BP of the patient by a well-known oscillometric method based on the change in the magnitude of the pulse wave obtained as the pressure oscillation of the cuff 10 in the course of the gradual change of the compression pressure of the cuff 10. _{SY S} , mean blood pressure BP
_MEAN and diastolic blood pressure BP _DIA are measured, respectively.

The blood pressure value display means 74 displays the systolic blood pressure value BP _SYS , the average blood pressure value BP _MEAN , and the diastolic blood pressure value BP _DIA measured by the blood pressure measuring means 70 on the systolic blood pressure display 40 of the display 36, The number is displayed on the blood pressure display 42 and the like, and is also displayed at a predetermined position on the recording paper 46 by the printer 38. The pulse wave amplitude storage means 76 sequentially stores the amplitudes of a plurality of cuff pulse waves generated during the blood pressure measurement period, that is, during the slow down period, in a predetermined storage area in the RAM 34. The pulse wave train display means 78
When the blood pressure measurement by the blood pressure measurement means 70 is completed, the amplitude of the cuff pulse wave stored so far is normalized, and the cuff pressure shaft 48 provided at a predetermined position on the recording paper 46 as shown in FIG. Within the two-dimensional coordinates consisting of the amplitude value axis 50, the printer 38 displays a bar graph showing the normalized plurality of cuff pulse wave amplitudes on a time axis showing elapsed time, that is, a cuff showing the compression pressure of the cuff 10. It is displayed along the pressure axis 48. The normalization is performed by setting the maximum amplitude of the pulse wave to a predetermined size, for example, the amplitude value axis 50 so that the distribution of the weak pulse wave train can be easily recognized.
And the other pulse wave amplitude is displayed as a relative magnitude with respect to the maximum amplitude. Further, the pulse wave train display means 78 displays marks 52 and 54 indicating the systolic blood pressure value BP _SYS and the diastolic blood pressure value BP _DIA measured by the blood pressure measuring means 70 along the cuff pressure axis 48.

The pulse wave amplitude display means 80 is a pulse wave discrimination circuit 2
The magnitude of the amplitude of the cuff pulse wave represented by the cuff pulse wave signal SM sequentially outputted from 4 is sequentially displayed on the pulse wave display 44 of the display 36. Since the display on the pulse wave display 44 is performed, for example, with the maximum amplitude of the dynamic range of the A / D converter 29 as 100%, a pulse wave train display of a normalized size is displayed. Compared to,
Indicates the absolute value of the magnitude of the pulse wave. Since the amplitude of the cuff pulse wave displayed on the pulse wave display 44 is an instantaneous value, the value displayed on the pulse wave display 44, that is, the length of the bar displayed by the light-emitting segment of the pulse wave display 44 is cuffed. The display is periodically fluctuated in synchronization with the pulse wave amplitude. Maximum amplitude determining means 82
Is the cuff pulse wave signal SM output from the pulse wave discrimination circuit 24.
Is calculated, and the maximum amplitude of the cuff pulse wave is determined by comparing the amplitude with the previous amplitude.

The maximum amplitude display means 84 functions as a cuff pulse wave intensity display means. The value indicating the maximum amplitude of the cuff pulse wave determined by the maximum amplitude determination means 82 is used as a pulse wave intensity display. Functioning pulse wave amplitude indicator 44
Then, it is displayed on the recording paper 46 of the printer 38. For example, in the pulse wave amplitude display 44, the maximum amplitude determination means 82
One light-emitting segment at a position corresponding to the value indicating the maximum amplitude of the cuff pulse wave determined by the above is continuously emitted, but the maximum amplitude determining means 82 updates the value indicating the maximum amplitude of the cuff pulse wave. Then, as shown by one light-emitting segment 56 in FIG. 2, one light-emitting segment at a position corresponding to the updated value is immediately and continuously made to emit light. When the blood pressure measurement is completed, the maximum amplitude display means 84 displays a value indicating the maximum amplitude of the cuff pulse wave determined by the maximum amplitude determination means 82 at a predetermined position on the recording paper 46,
For example, a graph is displayed at a position adjacent to the vertical axis of the two-dimensional coordinates. The maximum display value of the pulse wave amplitude indicator 44 or the recording paper 46, that is, the pulse wave amplitude indicator 4
4 or the maximum amplitude value of the cuff pulse wave that can be displayed on the recording paper 46 is the maximum output of the A / D converter 29 or 1 / the maximum output.
Although it is set to about 2, for convenience of quantitative display, the pulse wave amplitude display 44 or the recording paper 46 is scaled from 0 to 100.

FIGS. 5 and 6 show the electronic control unit 28.
It is a flowchart for explaining the main part of the control operation of,
FIG. 5 shows a pulse wave amplitude display routine, and FIG. 6 shows a blood pressure measurement routine. The pulse wave amplitude display routine of FIG.
It is preferentially executed at a relatively short period which is about the same as or longer than the sampling period of the D converter 29 and sufficiently shorter than the period of the cuff pulse wave.

In step SA1 of FIG. 5 (hereinafter, the steps are omitted), after the cuff pulse wave signal SM is read, in step SA2 corresponding to the pulse wave amplitude display means 80,
The instantaneous value of the cuff pulse wave represented by the cuff pulse signal SM is displayed on the pulse wave amplitude display 44. Next, in SA3, it is determined whether or not one cuff pulse wave has occurred, for example, whether or not a pair of maximum value and minimum value of the cuff pulse wave has occurred based on the cuff pulse wave signal SM. When the determination at SA3 is denied, this routine is ended.

If the determination at SA3 is affirmative,
At SA4 corresponding to the pulse wave amplitude storage means 76,
Amplitude A of one cuff pulse wave_MIs calculated, and RA
It is stored in a predetermined storage location prepared in M34. Next
The SA5 corresponding to the maximum amplitude determining means 82 and
And SA6 are executed. In SA5, the power generated this time
Pulse wave amplitude A_MAnd the amplitude A of the cuff pulse wave generated last time_M
^-1Difference (A_M-A_M ^-1) Is positive.
It is determined whether the amplitude of the pulse wave has increased. this
While SA5 is affirmed, this time at SA6
A of the cuff pulse wave generated in_MIs the maximum amplitude value A_Mmaxage
Stored or updated. However, the amplitude of the cuff pulse wave is
As the period of decrease will be negative in SA5
Then, the next SA7 is executed without executing the SA6.
Is performed. Thereby, the cuff stored in SA6 is obtained.
Maximum value A of pulse wave amplitude_MmaxIs substantially determined.

Next, at SA7 corresponding to the maximum amplitude display means 84, the maximum amplitude value A _Mmax of the cuff pulse wave stored at SA6 is changed to the pulse wave as shown by one light-emitting segment 56 in FIG. It is displayed on the amplitude display 44.

In the blood pressure measurement routine of FIG.
Then, it is determined whether or not a blood pressure measurement start button (not shown) has been operated. If the determination in SB1 is denied, this routine is ended, but if the determination is affirmed, SB2
In, by the air pump 18 is closed by and switching valve 16 starts, the compression pressure P _C of the cuff 10 is allowed to quickly increased. Next, in SB3, whether a pressing pressure P _C of the cuff 10 is boosted target value P _CM than that preset is determined. The boost target value P _CM is a high general value than the systolic blood pressure value of a living body, for example 180mmHg
A degree value is used.

[0022] Because the boost initially determines the SB3 is negative, by executing repeatedly SB2 less, quick increasing of the compression pressure P _C of the cuff 10 is continued. The compression pressure P _C is the boost target value P _CM of the cuff 10
When SB3 affirmative determination is reached, at SB4, by and selector valve 16 the air pump 18 is stopped is switched to the slow exhaust side, pressing pressure P _C of the cuff 10 is predetermined The pressure is gradually reduced at a moderate speed of about 3 mmHg / sec.

In such a slow pressure drop process, SB5
Then, whether or not one cuff pulse wave is generated is determined in the same manner as in SA3. While the determination at SB5 is denied, SB4 and subsequent steps are repeatedly executed.
In B6, the systolic blood pressure value BP _SYS , based on the change in the amplitude of the cuff pulse wave represented by the sequentially obtained cuff pulse signal SM,
A well-known oscillometric blood pressure value determining algorithm for determining the average blood pressure value BP _MEAN and the diastolic blood pressure value BP _DIA is executed, and the pulse rate and the like are determined based on the pulse wave interval. Then, at SB7, S
It is determined whether the blood pressure determination by B6 has been completed.

Initially, since the determination at SB7 is denied, SB4 and the subsequent steps are repeatedly executed. However, if the determination at SB7 is affirmative, at SB8, the switching valve 16 is switched to the rapid exhaust pressure state and the cuff is released. The inside of the cuff 10 is rapidly discharged, and the compression pressure of the cuff 10 is released. In this embodiment, S
B2, SB3, SB4, and SB8 correspond to the cuff pressure control means 7.
2 is supported.

At SB9 corresponding to the pulse wave train display means 78 and the maximum amplitude display means 84, the maximum value of the pulse wave amplitudes stored respectively in SA4 is set to a predetermined size, for example, the amplitude value. After the normalization process is performed to set the other pulse wave amplitude to the relative value with respect to the maximum value at 80% of the axis 50, the systolic blood pressure value BP _SYS , the average blood pressure value BP _MEAN , _{Alternatively} , the diastolic blood pressure value BP _DIA , the pulse wave train as a plurality of graphs showing the normalized pulse wave amplitudes, and the maximum amplitude value A _Mmax of the cuff pulse wave stored in SA6 are shown in FIG. Is displayed on the recording paper 46 by the printer 38 as shown in FIG.

As described above, according to this embodiment, the cuff pulse wave intensity display means, that is, the maximum amplitude display means 84 (SA
7, SB9), the maximum amplitude determining means 82 (SA5,
Maximum amplitude value A _Mmax of cuff pulse wave determined in SA6)
Is displayed on the pulse wave display 44 or the recording paper 46 of the printer 38. Since the maximum amplitude value A _Mmax of the cuff pulse wave indicates the intensity of the cuff pulse wave, when measuring the blood pressure of the living body using the automatic blood pressure measurement device 8, the strength or size of the pulse of the living body is objectively measured. Can be sequentially recognized. Therefore,
In addition to the blood pressure value of the subject, the strength or magnitude of the subject's pulse can be used as diagnostic or medical judgment data.

In this embodiment, the cuff pulse wave detecting device (cuff 1) is displayed by the pulse wave amplitude display means 80 (SA2).
0, the pressure sensor 14, and the instantaneous value of the cuff pulse wave amplitude sequentially detected by the pulse wave discrimination circuit 24) are displayed on the pulse wave amplitude display 44, so that the amplitude of the cuff pulse wave whose amplitude changes during blood pressure measurement is displayed. There is an advantage that the size, that is, the strength can be grasped.

Although the embodiment of the present invention has been described with reference to the drawings, the present invention can be applied to other embodiments.

For example, in the above-described embodiment, the maximum value A _Mmax of the cuff pulse wave amplitude is displayed on the pulse wave display 44 or the recording paper 46 of the printer 38 as a value indicating the pulse wave intensity. The maximum value S _Mmax of the area of one cuff pulse wave may be displayed as a value indicating the pulse wave intensity. In this case, a maximum area determining means for determining the maximum value S _Mmax of the area of one cuff pulse wave is provided in place of the maximum amplitude determining means 82, and one cuff pulse wave is replaced in place of the maximum amplitude display means 84. A maximum amplitude display means for displaying the maximum value S _{Mmax of the} area is provided. This maximum amplitude display means functions as cuff pulse wave intensity display means.

Further, instead of the area of one cuff pulse wave, a product of the wavelength and the amplitude of the cuff pulse wave may be used.

Further, in the above-described embodiment, the maximum value A _Mmax of the amplitude of the cuff pulse wave is regarded as a value indicating the pulse wave intensity, and the pulse wave display 4
4 or is displayed on the recording paper 46 of the printer 38, but may be displayed on either one of them. In this case,
The operation of displaying the maximum amplitude value A _Mmax of the cuff pulse wave in one of SA7 and SB9 becomes unnecessary.

As shown in FIGS. 2 and 4, the maximum amplitude value A _Mmax of the cuff pulse wave is displayed in the form of a bar graph on the pulse wave display 44 of the above-described embodiment or the recording paper 46 of the printer 38. However, it may be displayed, for example, in the form of a pie chart shown in FIG. In short, it only needs to be displayed quantitatively. In the pie chart shown in FIG. 7, the maximum value is set to 1000.

Further, in the above-described blood pressure measuring means 70, although the cuff pressure P _C has been determined blood pressure values of the living body on the basis of gradually changing the cuff pulse wave of the slow process to be lowered, thereby gradually boosted The blood pressure value of the living body may be determined based on the change of the cuff pulse wave in the process.

Further, the blood pressure measuring means 70 of the above-described embodiment is used.
Is configured to determine the blood pressure value based on a change state of the magnitude of the pressure pulse wave that changes according to the compression pressure of the cuff 10 according to the so-called oscillometric method, but according to the so-called Korotkoff sound method, The blood pressure value may be determined based on the Korotkoff sound that is generated and disappears according to the compression pressure of 10.

Further, the maximum amplitude determining means 8 of the above-described embodiment.
2 determines the maximum amplitude for each cuff pulse wave sequentially generated in the blood pressure measurement period, but determines the maximum amplitude of a series of cuff pulse waves stored up to that point immediately after the end of the blood pressure measurement period. It can be anything.

In addition, the present invention can be variously modified without departing from the gist thereof.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an automatic blood pressure measurement device according to one embodiment of the present invention.

FIG. 2 is a diagram for explaining in detail a display portion of the display device of the embodiment of FIG.

FIG. 3 is a functional block diagram for explaining a main part of a control function of the electronic control device according to the embodiment of FIG. 1;

FIG. 4 is a diagram showing a display example on recording paper by the printer of the embodiment of FIG. 1;

FIG. 5 is a flowchart illustrating a main part of a control operation of the electronic control device of the embodiment of FIG. 1, and is a diagram illustrating a pulse wave amplitude display routine.

FIG. 6 is a flowchart illustrating a main part of a control operation of the electronic control device of the embodiment of FIG. 1, and is a diagram illustrating a blood pressure measurement routine.

FIG. 7 is a diagram showing a pulse wave amplitude display example according to another embodiment of the present invention.

[Description of sign]

8: Automatic blood pressure measurement device 10: Cuff, 14: Pressure sensor, 24: Pulse wave discrimination circuit (cuff pulse wave detection device) 44: Pulse wave amplitude display (pulse wave intensity display) 38: Printer (pulse wave intensity display) 84): Maximum amplitude display means (cuff pulse wave intensity display means)

Claims (3)

[Claims] In the process of changing the compression pressure of a cuff on a living body, a blood pressure value of the living body is automatically measured based on a change in a cuff pulse wave which is a pressure oscillation generated in the cuff in synchronization with a pulse. An automatic blood pressure measurement device, comprising: a cuff pulse wave detecting device for sequentially detecting a cuff pulse wave which is a pressure vibration generated in the cuff; and a pulse wave intensity detecting the intensity of the cuff pulse wave detected by the cuff pulse wave detecting device. An automatic blood pressure measurement device having a pulse wave intensity display function, comprising: cuff pulse wave intensity display means for displaying on a display. 2. The apparatus according to claim 1, further comprising a maximum amplitude determining means for determining a maximum amplitude value of the cuff pulse wave during a measurement period of the blood pressure value, wherein the cuff pulse wave intensity display means includes a cuff determined by the maximum amplitude determining means. 2. The automatic blood pressure measurement device having a pulse wave intensity display function according to claim 1, wherein a maximum amplitude value of the pulse wave is displayed on a pulse wave intensity display as a value indicating the intensity of the cuff pulse wave. 3. A cuff pulse wave intensity display means for determining a maximum area value of the cuff pulse wave during a measurement period of the blood pressure value, wherein the cuff pulse wave intensity display means determines the cuff determined by the maximum area determination means. 2. The automatic blood pressure measurement device having a pulse wave intensity display function according to claim 1, wherein the maximum area value of the pulse wave is displayed on a pulse wave intensity display as a value indicating the intensity of the cuff pulse wave.